Lubricants



Patented Sept. 26, 1944 Roy Moore and F. Nelson, Scarsdale, N. Y., andWindsor Norman W. Faust, Port Arthur,

TexL, assignors, by mcsne assignments, to The Texas Company, New York.N. Y., a corporation of Delaware No Drawing. Application November 8,1940,- Serial No. 364,840

9 Claims. ,(01. 252-43) 'This invention relates to lubricants, and more.particularly to soap-containing lubricants of improved appearance andstability.

Lubricating 'oils are frequently compounded with metallic soaps to yieldfluid to solid products, In these products, as ordinarily prepared,there is a tendency for the oil to'separate from the compounded product,and this tendency may be particularly pronounced in the fluid andsemifiuid products. The ordinary products also have a cloudy or opaqueappearance, and for purposes of producing a product of improvedappearance and stability, it i desirable to overcome this defect andprovide a clear, transparent lubricant.

It is an object of this invention to provide novel stabilizing agentsfor soap-containing lubricants, which stabilizing agents also have theproperty of overcoming the cloudy or cheque appearance of thelubricants. s

It is a further object or this invention to provide an improved methodof preparing soap-containing lubricants involving intensive milling ofthe lubricant in the presence of stabilizing agent's, whereby thestability of the lubricants is further improved.

It has been found that certain well-known emulsifiers have the propertyof stabilizing soapcontaining lubricants and improving the appearance ofsoap-containing lubricants. Inan intensive investigation of the additionofemulsiflers to soap-containing lubricants, we have found that certainsulphonates improve theproperties of this type of lubricant, and that,in general, other emulsifiers show little or no improvement. Thesulphonates which have been found to be particularly eilective are thepetroleum sulphonates known as mahogany sulphonates, i. e., theoil-soluble sulphonate's produced by tI'QItr ment of petroleum oils, orfractions or extracts.

thereof, with sulphuric acid or other equivalent sulphonatins agents.These sulphonates are preferably employed; in the form of their alkali.metal salts, for example, I proportion of petroleum sulphonates toproduce the desired stabilization of the lubricantdepends.

upon the soap content of the lubricant and, :in

general proportions of 2 to 20% of petroleum sulphonates, based iective.

While the stabilizer of this invention may be added to anysoap-containing lubricant with'favorable results, wehave found that thestabiliaers are most eflective for liquid lubricants-contain ing fromabout 0.5 to 6% of a water-insoluble;

on the soap content. are sition of this invention, is

soap, such as lime soap. One type of liquid lubricant, designedparticularly for the lubrication of textile machinery, which ismaterially improved by the stabilizers and method of preparaa lubricantcomprising a mineral lubricating oil and from about 0.5 to 6% lime soapderived from animal or vegetable oils and fats or mixtures thereof. Thelime soap in this type of lubricant may be replaced by a mixed base soapcontaining a major proportion of calcium soap and a minor proportion ofsodium soap.

In order to more fully disclose the invention,

the following example is given, but it is to be understood that theinvention is not limited thereto.

A base composition was prepared from the following ingredients:

of the lubricating oil were added slowly while agitating and allowing tocool until the proportion of soap was about 15% oi the totalcomposition. The resulting product'had the appearance of a cup grease.

the sodium salts. The

In preparing a. lubricant containing about 2.5%

. mp. this base composition was thinned with a ortion of the requiredamount of lubricating oil (300 viscosity naphthene base oil),andsuiilcient commercial mahogany sulphonates. containing about 42% ofsodium mahogany 'sulphonates, was added to give a proportion of sodiummahogany sulphonates oi about 2.5% oi the soap content. This required aproportion of about 6% of the commercial mahogany sulphonates, based onthe soap content.- The mixture of base composition, lubricating oil. andemulsifier was heat- 'ed with agitation in about 300 to 310, F. and

maintained at 200 to 810' 1''. until the couiposi- -tion wassubstantially dehydrated. After allowing the substantially dehydratedmixture to cool to about 200 F. suflicient water was incorporated in themixture with agitation to give the composition maximum stability. .Ingeneral, the

proportion of water for maximum stability is. from 0.1 to 0.5%, and inthis example the'pro-.

portion was about 0.3% of the final composition containing about 3.5%soap. The remainder of.

the lubricating oil was then added with agitation. It is preferableto-add the lubricating oil in portions as described above, but it is tobe understood that all of the required amount oflubrlcating oil may beadded before th step of heating to substantial dehydration.

The resulting lubricant was a clear, transparent product which showedonly very slight oil separation in storage for six months. However. tofurther improve the product against 011' separation, it was subjected tointensive shearing stresses by running through a colloid mill severaltimes. The intensive mixing in the colloid mill resulted in materialimprovementin the product especially with respect to oil separation.After six months storage the oil separation inthe product which had.been run througha colloid mill was so slight as to'be negligible .forall practical purposes.

The lubricating oil used in'the example was a naphthene base oil havingthe following characteristic's:

Gravity,- A. P. I- 20.8 Flash, F 3'70 Fire, F I 426 Viscosity, S. U. at130 IL-.. 816 Color, Lovibond 6" cell 100 Pour, F 20 .lubricating oil,about 0.5-6.0% by weight of a lime soap, and about 2-20% by weight,basedon the lime soap content, of an alkali metal petroleum mahoganysulphonate to maintain the transparency of the lubricant and tostabilize the lubricant against oil separation.

3. A liquid lubricant comprising a petroleum lubricating oil, about0.5-6.0% by weight of a mixed base soap containing a major proportion ofcalcium soap and a minor proportion of sodium soap and about 2-20% byweight, based on the mixed base soap content, of an. alkali metalpetroleum mahogany sulphonate to maintain the transparency of thelubricant and to stabilize the lubricant against oil separation.

4. A liquid lubricant comprising a petrolemn lubricating oil, from0.5-6.0% of a lime soap, from 0.1-0.5% water, and a proportion of analkali metal petroleum mahogany sulphonate of.

the order of 2-2070 of the linie soap content.

5. A method of stabilizing a polyvalent metal soap-containing liquidlubricant which com- I prises incorporating in the lubricant a smallproportion 'ofan alkali-metal petroleum mahogany suiphonate or the orderof 2-2o% of 1 the polyvalent soap content. 1

8. A-method of stabilizing a polyvalent-metal soap-containing liquidlubricant which comprises incorporating in the lubricant a smallproportion of an alkali metal petroleum mahogany sulphunate, based onthe polyvalent metal soap content, and subjecting the mixture tointensive shearing stresses.

7. A method of stabilizing a polyvalent metal soap-containing liquidlubricant which comprises Any suitable petroleum lubricating oil, suchas a distillate or refined residual oil, having a viscosity of from 70at 100 F. to about 150 at 210 F. can be employed. For a textilelubricant, a lowerviscosity oil of about 300 or below at 100 F. ispreferred.

Other grades of lubricant having soap contents of from about 0.5 to 6%may be prepared as described in the specific example, or by equivalentmethods, with the modification that the proportion of lubricating oil isadiusted to result in lubricants of the desired-soap content.

Obviously, many ,modifications and variations of the invention, ashereinbefore set forth, may

incorporating in the lubricant about 2-20% by weight, based on-thepolyvalent metal soap content, of an alkali metal petroleum mahoganysulphonate. andpaseing the mixture through a col- 40 loid mill.

8. A method of preparing a stable pclyvalent metal soap-containingliquid lubricant of improved appearance and transparency which comprisesmixing a mineral lubricating oil with about 0.5-8.0% by weight of awater-insoluble polyvabe made without departing from the. spirit and]scope thereof, and therefore only such limitations should be imposed asare indicated in the 6B appended claims. What we claim is:

1. A--liquid lubricant comprising a petroleum 1 lubricating oil,water-insoluble polyvalent metal soap in a proportion to maintain thefluidity of'thelubricant at ordinary atmospheric temperatures, and asmall percentage .of an alkali metal petroleum mahogany sulphcnate,based on the polyvalent metal. soap content. to

2. A liquid lubricant comprising a petroleum lent metal soap, adding asmall proportion of an alkali metal petroleum mahogany sulphonate,

about 240% by weight of the lime soap content, I heating to effectsubstantial. dehydration of the maintain the transparency of thelubricant and 06 to stabilize the lubricant against oil separation.

mixture, partially cooling, and then-adding from' ture through "acolloid mill.

. ROY I". NELSON. WINDSOR. MOORE. NORMAN w. FAUST.

0.1-0.5% by weight of water, and passing'the mix cfin'rI IcATEpFCORRECTION.

Pa -N 2 558 959,

ROY F. NELSON, ET AL.

It is hereby certified that error appears in theprinted specification ofthe above numbered -pewseht requiring correction asfollows: Page 2second column, line 26, claim 5., before the vyord "soap" insert met'a1and tha t the said Letters Patent should be. rearl W1 that the same mayconform to the'record of the Signed and sealed this 16th day of January,A. D. 19b.5.

case in the P atent Office.

Leslie Frazer (Seal) Aching Commisei'oner of Patents,

' September 26, 19%.

th this correction therein

